Assessment of Nicotine Metabolism Among Underserved Pregnant Women from NE SCRIPT Principal Investigator: Parker, Donna R. Project Summary/Abstract: Smoking during pregnancy is of particular concern because smoking affects not only the health of the woman but also the health of her developing fetus. The effect of tobacco exposure on the infant's birth weight may have long-term consequences. Although the exact effect of in utero exposure to tobacco is unclear, fetal growth appears to be a predictor of coronary heart disease in later life. The estimates of the relative risk of prenatal smoking on fetal outcomes, however, may be biased due to misclassification of maternal self-reports of smoking during pregnancy. A number of biomarkers have been used to validate self-reports of smoking although results have varied. This project proposes a one-year pilot study to explore the use of a novel biomarker of nicotine metabolism, the ratio of trans-3'-hydroxycotinine to cotinine (3-HC:C), as an estimate of nicotine exposure from tobacco during pregnancy. The study will use existing data and existing urine specimens from a predominately low-income, multi-ethnic population of pregnant women who participated in the New England SCRIPT randomized clinical trial (Smoking Cessation and Reduction in Pregnancy Trial). The objectives of the study are to 1) explore the stability of the 3- HC:C ratio as a measure of prenatal tobacco smoke exposure between the 1st and 3rd trimesters and 2) to examine the use of the 3-HC:C ratio in relation to infant birth weight. This study will measure both cotinine and hydroxycotinine levels in urine samples using state-of-the-art methodology- liquid chromatography/atmospheric pressure ionization tandem spectrometry. Changes in the 3-HC:cotinine metabolism during pregnancy will be examined by racial/ethnic subgroups due to known differences in nicotine and cotinine metabolism. We will also examine differences in the 3-HC:cotinine ratio between the prenatal and postpartum period. The proposed pilot study provides an exciting opportunity to examine this novel biological index of nicotine metabolism (the 3-HC:cotinine ratio) as an estimate of the effect of smoking during pregnancy among a multiethnic population of pregnant women from New England. Findings from this study will be shared both locally and nationally and if these results prove promising, they will provide pilot data needed in preparation for an R01 submission. PHS 398/2590 (Rev. 04/06) Page Continuation Format Page Assessment of Nicotine Metabolism Among Underserved Pregnant Women from NE SCRIPT Principal Investigator: Parker, Donna R. Project Narrative: Self-reports of smoking during pregnancy do not accurately assess smoking status because pregnant women are often influenced by a desire to please investigators and/or appear to be successful in quitting. Misclassification of smoking status of pregnant women could lead to underreported prevalence and cessation rates as well as untreated health care needs during prenatal care. Since the public health significance of smoking during pregnancy continues to be substantial, biomarkers are needed to confirm smoking status and a novel biomarker, the trans-3'-hydroxycotinine to cotinine will be evaluated to confirm smoking status among a multiethnic group of pregnant women from New England. PHS 398/2590 (Rev. 04/06) Page Continuation Format Page [unreadable] [unreadable] [unreadable]